Villain

means simply one attached to a villa or farm. In feudal times
the lord was the great landowner, and under him were a host of tenants
called villains. The highest class of villains were called regardant, and were annexed to the manor; then came the Coliberti or Bures, who were privileged vassals; then the Bordari or cottagers (Saxon, bord, a cottage), who rendered
certain menial offices to their lord for rent; then the Cosects,
Cottarii, and Cotmanni, who paid partly in produce and
partly in menial service; and, lastly, the villains in gross, who were annexed to the person of the lord, and might be sold or
transferred as chattels. The notion of wickedness and worthlessness
associated with the word is simply the effect of aristocratic pride and
exclusiveness- not, as Christian says in his Notes on Blackstone, “a proof of the horror in which our forefathers held all service to
feudal lords.” The French vilain seems to connect the word with vile, but it is probable that vile is the Latin vilis vile (of no value), and that the noun villein, except by way of pun. (See Cheater.)

“I am no villain [base-born]; I am the youngest son of Sir Rowland
de Boys; he was my father, and he is thrice a villain [rascal] that
says such a father begot villains [bastards].” —Shakespeare: As You
Like It, i. 1.